Astronomers are trying to figure how a rock shaped like a jelly doughnut has suddenly appeared out of nowhere on the surface of Mars. It does not appear in previous imagery of the rock's location on the rim of the Endeavor Crater.

The doughnut rock, slightly rarer than a cronut, has been dubbed "Pinnacle Island" and showed up on the planet's surface sometime between December 26 and January 8.

Not to worry though, NASA is on the case. "We’ve taken pictures of both the doughnut part and the jelly part," investigator Stephen Squyres told The Washington Post. Thorough!

The dark-red portion has lots of sulfur and magnesium, as well as twice as much manganese as anything previously measured on Mars. The results have deeply confused NASA scientists, Squyres said and have inspired heated debates about what this could mean.

"We have looked at it with our microscope. It is clearly a rock," Squyres also announced to a shocked audience probably.

The discovery comes on the tenth anniversary of the rover Opportunity's landing on Mars. Initially planned for a three-month operation, it's still ticking along, having gone 38 kilometers in its lifetime, 37 more than expected. "It’s a well-made American vehicle,” deputy principal investigator Raymond Davidson told The New York Times—not realizing the oxymoron of using both "well-made" and "American" (zing!!!).

Scientists believe that the rock most likely appeared when Opportunity yanked it out of the dirt. They hypothesize that the ten-year-old robot's non-functioning front-right wheel "dragged across the rock and flicked it out of the ground to its new location." The second, less likely idea is that the rock is crater ejecta from a foreign body striking the planet elsewhere.

So we may never know where Jelly Doughnut Rock really came from. But we'll still have this amazing quote: "We have looked at it with our microscope. It is clearly a rock."

This article is from the archive of our partner The Wire.

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